Oil burner and control mechanism therefor



F. R. wg-n'rcoMB OIL BURNER AND CONTROL MECHANISM THEREFOR Filed nec. 2s, 193s March 19, 1940.

Peiented Mer. 19,1940

PATENT orties i 21,194,133 y on. BURNER. AND CONTROL MEoHANisM THEREFOR f Forrest R. Whitcomb, Winchndn, Mass.

estimation December 23, 1936, serial No. 117,313

, Claims. .This invention rentes 'maquis fuer burners and Ito protective devices therefor arrangedto shut down the burner when it' isoperating im-v properly and partiimlaryv when` anA excessive amount of liquid oil has escaped therefrom.

The invention is concerned particularly With liquid fuel burners, as oil burners, of the vaporizing' type, although itis `notnecessarily restricted tosuchitype o'burners. v In an oil burner of the vaporizing type the oil is vaporized in a' heated generator and the vapor is discharged usually under substantial pressure into a mixing tube Where it draws in sunicientl air for combustion and the combustible mixture 23' passers into the burner body and issues from the burner orices Where it burns. If' the generator is insuliciently heated at the time of starting the burner in operation the vapori'zation of the oil is not complete and raw oil can `iiovvvinto thev `Hence an object of the present invention is the provision of means for collecting the raw oil that may be discharged into the burner and for stopping the flow of oil to the burner when thev accumulation is excessive.

A further Aobject, is the provision of an improved form of mechanism `for stopping the flow of oil tothe burner, the mechanism being operated' by the discharge of a predetermined amount of rawl oil yinto the burner and being self-locking inuan operated condition so that it must be'manually unlocked and reset before fuel can again be supplied to the burner and generator for further operation thereof.

The protective mechanism includes a float operated by the raw oil discharged into the burner to cut oi the supply of oil tothe burner. yIt is a further object of, the inventiony to vprovide means for delivering vadditional oilv4 to the float chamber at the time the float is about in a lovv-A stopping position`,so as to insure a positive and quick movement ofthe floatitof an operated posi.'

tion thereof. l y Y, l Another objectdf the invention isthe provision of protective apparatus as above described having means by which it is 4operated to shut off the supply of oil to the burner in the event of agiangerous rise of temperature in the vicinity of the apparatus and the burner.

Another object of the invention is the provision of protective apparatus as above outlined having means Which eifects its operation to shut on7 the flow of oil tothe burner when the pressure 4in the supply line becomes unduly high, as'occasioned by the partial Aor' complete clogging of the oil vapor orice.

When a vaporizing type of oil burner has the oil sup-ply leading to its generator shut ofi'i'or the purpose of shutting vdown the burner at the time s the generator is hot there is a considerable amount of voil in the hot generator. The oil continues to be Vaporized and the Vapor to discharge into the burner for sometime after the o il has been shut olf. This' means that the ame is not 20 extinguished immediately or, if the oil'supplyhas been shut off due to improperfoperation of the burneigsuch as caused theflame to ybe extinguished, for instance,the unconsumed oil vapor will collect in the gas passages leading from the burner and flow into the surrounding atmospl'iere,

not only producing an objectionable odorbut also a fire hazard'. 4

Hence another object of the present invention `is the `provisionjof means for interrupting the K oW of fuel to the burner and alsofor venting the oil supply line 'so as to relieve the pressure on the lineand to 'discharge roil from the generator and thereby to immediately extinguishv the ir'e and to prevent the discharge of material amount of l obnoxious and combustible gases, `and also liquid fuel, from the generatornozzle.

Another object of the invention is the provision of manual means by yvvliich the flow of fuel to the generator can be interrupted and the pres- 40 surein the generator yrelieved and the oil therein Withdrawn.

A further object oi the invention is the provision of protective apparatus for an oil burner receiving pressure oil from almotor driven pump,

the protectiveapparatus being arranged to shut ou ydelivery of oil through the line connecting the lpump with the burner and to change ythe oil pressure in a part of the line suiiciently to eifect 50.

the interruption of the motor circuit and thereby to stop the operation of the pump.

Another object is generally to improve the constructionl and operation of oil burners and protective and control apparatus therefor. 5v5

Fig. 1 is a diagrammatic View of an oil burner system with which the present invention is associated.

Fig. 2 is a longitudinal sectional elevation through the lioat controlled protective apparatus of Fig. 1.

The oil burner with which the present invention is associated comprises an entrance casing l!! for the combustible mixture of oil and vapor, and the burner tube l2 into which the combustible mixture flows and discharges through orifices i4. The incoming oil is supplied under suitably high pressure through a pipe I6 and passes into a generator I8 which is herein shown as a continuation of the pipe i6. The generator I3 passes above the burner tube I2 and in suinciently close relation with the llame or heated gases from the burner orifices so that it is heated suirlciently highly to vaporize the oil in the generator before the oil arrives at the front end of the generator.

rIhe oil vapor is discharged through the orifice of a burner tip or nozzle 20 into the inlet of the burner casing i0 where it entrains a suihcient volume of air to form with the oil vapor a combustible mixture.

The oil for the burner is contained in a suitable tank 22 andis drawn from the tank and is pumped under pressure by a suitable pump 24 operated by the electric motor 26. The oil from the pump passes through a pipe 28 and thence into the pipe l5 through the protective or control apparatus generally indicated at 30.

When the heat of the generator is insufflciently high to properly vaporize all oi the oil, as when the generator is not heated enough prior to starting the burner in operation, or has cooled down after the generator flame has been accidentally extinguished, or is cool for other reasons, raw oil will be discharged into the burner. The entrance casing lll is provided with a cup or reservoir 32 in which the raw oil is collected. The cup is below the inner face of the bottom wall of the burner tube and the tube preferably is inclined toward said cup so that the raw oil and the condensed oil vapor can flow into the cup and thence into the protective apparatus 38 to operate said apparatus to shut ofi the supply of oil to the burner when the collection of raw oil becomes excessive.

The protective apparatus 38, illustrated in cross section in Fig. 2, comprises a casing having a bottom wall 34 and the generally elliptically shaped upstanding side Wall 36. The casing is open at the top and is closed by a cover 38 secured removably in position by screws 40, see Fig. 1. The casing is traversed in approximately the middle thereof by a partition wall 42, thereby separating the casing into two compartments 44 and 46. Oil from the burner cup 32 flows by gravity through a pipe 48 and through the cover 38 into the compartment 44 where it collects.

The partition wall 42 is provided with an upstanding cylindrical enlargement 56 having a cylindrical bore 52 which extends substantially to the bottom wall 34 and has a conical seat 54 at its bottom end, which seat, and the cylindrical enlargement, is traversed by an oil passage 56 that establishes communication between the two chambers 44 and 46. Such communication is normally interrupted by a valve stem 58 disposed loosely in said bore 52 and having a conical seat that normally interrupts the continuity of the passage 56. through the cover 38 and can be engaged manu- The valve stem projects loosely ally and raised to permit oil to ow from the chamber 44 into the chamber 46. Oil escapes from the chamber 4G through a pipe 6D and back into the supply tank 22.

The cover 38 above the chamber 46 is provided with an upstanding valve-enclosing boss E2 having a vertical cylindrical passage G4 therethrough which is internally screw-threaded at least at its upper and lower ends` The upper end of the boss, and said passages, is provided with an enlarged recess 68 surrounding the upper end of the passage 64.

A cap 68 has an annular rib l0 located in said passage and seated upon a packing ring 'l2 against which it is held firmly but removably by a pair of bolts 14, one of which is shown in Fig. l. The cap 'I8 has an annular recess 'I8 in its lower end which surrounds the upper end of the passage 64. The cap has a fuel passage 'I8 therethrough which conducts fuel to the recess T6 and into which the high pressure pipe 28 from the oil pump 24 is connected. A strainer 80 is interposed between the passage 'i8 and the recess or chamber 'I6 'for the purpose of filtering the oil flowing from the pipe 28.

An upper valve bushing 82 is screw-threaded in the upper end of the passage 64 and is provided with a valve stem 84 which is vertically movable therein. The stem is provided with an enlarged head 8B at its upper end which overlies the bushing and when seated thereupon shuts 01T the now of oil through the valve stem passage in the bushing. The valve stem is provided with flutes or longitudinal oil passages 88 in its side wall through which oil can flow when the head 86 is elevated above the top of the bushing.

Under normal conditions of operation the valve is maintained in elevated position so that oil can flow through the bushing and into the intermediate part of the passage 54 and thence into a passage 9U that opens into the passage 54 and thence into the pipe i6 screw-threaded into the discharge end of said passage 88 and leading to the generator and burner.

A second, or lower, valve bushing 82 is screwthreaded into the lower end of the passage 64 and has a valve stem passage 94 therethrough provided with a reduced conically shaped upper end 96. A fluted valve stem 98 is reciprocable in said passage and has a conical end 100 which under normal conditions is seated on the conical end 86 of the valve passage to prevent flow of oil through the bushing. lThe valve stem 98 is provided with an extension 102 that projects above the bushing and engages a depending projection H14 which is adjustably screw-threaded into the bottom end of the stem S4 of the upper valve. The arrangement is such that when the lower valve is closed the upper valve is open and l;

vice versa. The amount of elevation of the head 88 of the upper valve above its seat on its bushing is relatively slight, being only a few thousandths of an inch, which amount is sufficient to pass the requisite amount of oil. The upper valve is normally held open and the lower valve held closed by the float controlled mechanism associated therewith.

The oat controlled mechanism includes a float member 106 disposed in the oat chamber 44 and pivotally connected to the ends of a pair of lever arms |08 which are located above and traverse the partition wall 42 and are pivoted close to their other ends at Ill) to a supporting frame H2 located beneath the valves. Said lever arms |08 the vapor is reduced to atmospheric pressure andv `when operating it and hence there is little danger of they valve cramping or sticking.

The weight of the oat, when there is little oil in the fioat chamber -44,is sunlcient'to maintain 'the lower valve 98 in closed position and the upper valve 86 in open yposition Vso 'that oil canflow freely from the oil kpump to the burner. `If,

however, there is a iiow of raw oil into the burner or a condensation of oil vapor therein the oil ows into 4and accumulates in `the float chamber 44 and ultimately raises the float sufiicientlyl to effect the opening of the lower valve and the closing of theupper valve. As a consequence the oil flow from the pump to the burner is cut off so that kfurther discharge kof raw oil into the burner is prevented.` v

Due to theopening ofthe low'ervalve the pipe |16 is permitted to vent immediately 4through said valve into the interior of the casing 36 yan'd'par vticularly into the chamber 46 thereof, theinterior of the casing being at atmospheric pressure. a consequence the oil in thegeneratory I8 is so has no tendency to ow out ofthe nozzle 20. If there is a suicient amount of vapor all'of the oil of the pipe and also the vapor will `pass into -the'casing 36 and the vvapor will ultimately condense therein. With this arrangement discharge of gas from the burner nozzle ceases immediately the float operates and hence there 'can be vno liberation of obnoxious andfc'ombustible' gases. If

theiiame is burning at the time the device opf crates the flame is immediately extinguished.

Means are providedwhichv locks the mechanism in an operated position so that the burner, cannot be restarted without iirst resetting themechanism. For this purpose the'float lis'provided with a stem |20 which is freely vertically ymovable in the cover 38. The upper end of the stem is provided with a manually-engageable knob |22. A. latch |24 is loosely lpivoted at |26 yto an upstanding boss |23 of the cover and has its upper end inclined toward and normally bearing against the knob |22. WhenA theifloat 'is raised to an operated position by reason of 'an accumulation of oil in the float chamber the knob '|22 passes above the upper end of the latch sothat the latch falls by gravity under the knob, or the hub |2211 thereof, thereby holding the oat in an elevated position and the upper valve 86 closed and the lower valve 98 open until the latch is restored manually to its original position and the float permitted to fall after the chamber 44 has been drained of oil by raising the valve 58.

The iioat can be raised manually at any time by engagement of the knob |22 and will be locked automatically in an operated position' by said latch. The manual raising of the oat effects the` venting of the generator and the'irnmediate extinguishment of the burner name in the manner above'described.

The valve 'mechanism is also adapted to y,be operated `automatically in` the event o'f a vdangerous velevation of temperature ofthe ambient atmosphere, such as may result .from burning 5oilfoutside the burner. To this end the frame 2 "that supports the valve operating lever .|08

is pivotally mounted at |30 to a :depending .lug

|1332 ofthe cover lon the side `of the axes of .the

valves oppositethe pivot I| l0 for the Valve Vop`erat-- ingflever. The freeend of the'frame is connected to la rod v[3'4'whichpasses .loosely `throughthe "cover "38 and is hooked to the lower end of a fusible `link Amember |36, the upper endfof which `is suitably anchored removably Ito a partof the ica-p t8. A'fcompression spring |36 encircles the rod |34 and'bears against the cover 'and against lthe frame 'fl-.|12 in a direction toforce the 'frame downwardly. When the link melts due to excessive-"heat the spring-forces the 'frame "downwardly and gconsequently operates `to open `the vlower valve and `closefthe upper valve and vshut on 'thesupply of oil-to the burnerand to :relieve `the generator of-oil. "The devicecanibe reset fby installing a new' link 36. The device is operative *by gravity andthe pressure of oil onthe valves end the valvebushing Q2 has a cup :|49 .thereon lwhich -surrounds the lower end of the valve stem '96 and receives oil that is'discharged fromthe utes thereof. 'I'he oil is conducted through a duct |42 into 'the float *chamber vt4. The arrangement"is such that .when the float hasbeen yraised high enough to slightly Vopen the lower `valve oil :discharged 'therethrough ows into the lfloat-chamberA Aand rapidly raises the oil level therein to-cause the float to move-rapidly and 'positively `up into its rffully=operated position.

The mechanism yis also arranged to .shut ofi' ithe flow of `oil to Athe burner if the oil pressure in the generator becomes unduly highas may-be occasioned by a partialor completestoppage of the burnerorilce, or by unauthorized tampering -with=the pressure regulating devices. This result is secured by av proper adjustment ofthe weights of `the-parts.' 'It willvbe appreciated that the oil pressure in the pipe I6 acts upon` thelower valve L98 in `a direction to yopen '.itand that this valve is heldclosed by the-weight of Jthe float andthe associated mechanism. When the voil pressure' becomes sufcientlyyhigh the valve 98 is Amoved downwardly thereby, andi caused to open. The downward movement of the valve 98 enects the closingof the upper valve84, thereby vshutting off thev oil supply. Oil'from theipipe I6 flows through the open valve 98 and into the .float `comprising cooperating stationary .and movable contact members |44 and |45, respectively. vSaid movable Contact member l|46 is moved :into and out of engagement with 'the stationary contact member |44 `by an expansible bellows :|43 or equivalent i operated i by the pressure of -oil in the pipe line 28 connected to the pump. YWhen the oil pressure, is suiciently high the bellows maintains the motor circuit closed. When the pressure drops below a predetermined minimum value as determined by the adjustment of the bellows, the bellows contracts and thereby opens the motor circuit and stops the pump and motor.

The drop of pressure necessary to eiect sufficient contraction of the bellows to open the circuit controller occurs immediately both the upper and lower valves are open at which time the pump discharges at substantially atmospheric pressure into the casing and into the float chamber thereof. Thus the operation of the control mechanism, either automatically or manually, effects the stoppage of the motor and pump.

After the control apparatus has been reset the motor can be restarted by manually moving the movable contact member into engagement with the stationary contact member against the elasticity of the bellows and holding the movable contact member in such position until sucient oil pressure has again been built up in the bellows. f

In the claims the term oil comprehends any liquid fuel.

I claim:

1. The combination of an oil burner, a source of liquid oil, a pipe conducting oil from said source to said burner, a shut-orf valve in said pipe, a vent valve opening into said pipe between said shut-off valve and said burner, and means responsive to the ow of liquid oil from said burner operative to close said shut-oil valve and open said vent valve to stop the flow of oil through said pipe and to immediately relieve the pressure at said burner.

2. The combination of a vaporizing type of oil burner having a Vapor generator, means for supplying oil to said generator, and means for cutting off the supply of oil to said generator and means independent of the oil supply means and automatically responsive to a condition of the burner for venting the vapor pressure in said generator.

3. The combination of a vaporizing type oil burner having a vapor generator, means for supplying liquid oil to said generator, and means responsive to an abnormal condition of said burner for shutting o" the supply of oil to said generator and for immediately venting oil and vapor from said generator between the generator and the oil supply means.

4. The combination of a vaporizing type oil burner having a vapor generator, a source of pressure oil, a pipe for conducting oil from said source to said generator, means for controlling the supply of oil to said generator, and automatic means responsive to a condition of the burner for venting said pipe between said source and said generator for relieving oil from said generator.

5. The combination of a vaporizing type oil burner having a vapor generator, a source of pressure oil, a pipe for conducting oil from said source of said generator, and means responsive both to an abnormal operating condition of said burner and to manual control for shutting c the supply of oil to said generator and for venting said pipe between said source and said generator for relieving said generator of oil.

6. The combination of a vaporizing type oil burner having a Vapor generator, a pressure oil supply, a pipe line for conducting oil from said supply to said vaporizer, valve mechanism in said pipe line operative to prevent the flow of oil through that portion of the pipe leading from said `valve mechanism to said generator and to vent the oil in said portion of the pipe, and means for operating said valve mechanisms concurrently.

`'7. The combination of a vaporizing type oil burner having a vapor generator, a pressure oil supply, a pipe line for conducting oil from said supply to said vaporizer, valve mechanism in said pipe line operative to prevent the flow of oil through that portion of the pipe leading from said valve mechanism to said generator and to vent the oil in said portion of the pipe, and operating means for both said valve mechanisms concurrently responsive to an abnormal condition of the burner.

8. The combination of a vaporizing type oil burner having a vapor generator, a pressure oil supply, a pipe line for conducting oil from said supply to said vaporizer, valve mechanism in said pipe line operative to prevent the flow of oil through that portion of the pipe leading from saidv valve mechanism to said generator and to vent the oil in said portion of the pipe, and operating means for both said valve mechanisms concurrently responsive to an abnormal condition of the burner and also to manual control.

9. The combination of a vaporizing type oil burner having a vapor generator, a pressure oil supply, a pipe line for conducting oil from said supply to said vaporizer, valve mechanism in said pipe line operative to prevent the flow of oil through that portion of the pipe leading from said valve mechanism to said generator and at the same time to vent the oil in said portion of the pipe, operating means for said valve mechanisrn responsive to an abnormal burner condition, said valve mechanism including a valve for closing that portion of the pipe between it and said oil supply, and another valve for opening that portion of the pipe between it and said generator to a lower pressure.

10. Control mechanism for oil burners comprising means providing an inlet for pressure oil,

an outlet for theol to the burner, and oil-levelrently therewith for venting said outlet.

11. Control mechanism for oil burners comprising means providing an inlet for pressure oil,

an outlet for oil to the burner, a valve for closing said inlet, a Second valve for opening said outlet to the atmosphere, and valve operating means for both valves normally holding said first valve open and said second valve closed and operative into a position to close said rst valve and open said second valve.

12. Control mechanism for oil burners comprising means providing an inlet for pressure oil, an outlet for oil to the burner, a valve for closing `said inlet, a second valve for opening said outlet to the atmosphere, valve operating means for both valves normally holding said rst valve open and said second valve closed and operative into a position to close Said first valve and open said second valve, and oil level responsive means for operating said valve operating mechanism.

13. Control apparatus for oil burners comprising means providing an inlet for pressure oil,

an outlet for oil to the burner, a passage connecting said inlet and outlet, a valve for closing said inlet, a second valve for opening said passage to the atmosphere, valve operating mechanism controlling said valves and normally biased in a direction to opensaid 'first valve and toclose' said' second valve, means providing "a float chamber adapted to receive oil from 4the burner; a 'float in saidchamber in control of said valve operating mechanism andmovable inr response to a suicient elevation ofv oil in said float chamber intol a position to close said first valve and to 4open said second valve, and means for releasably locking said valve operating mechanism in the operated position thereof.

14. Control apparatus for oil burners comprising means providing an inlet for pressure oil, an outlet for yoil to the burner, valve mechanism for closing said inlet and for opening said outlet to the atmosphere, fluid level responsive means for operating said valve mechanism, and latch means vfor releasably looking means and valve mechanism in the operated position -thereof 15. Control apparatus for oil burners comprising means providing an inlet for pressure oil, an outlet for oil to the burner, a passage connectingsaid inlet and outlet, avalve for closing said inlet, a second valve for connecting said passage to the atmosphere, operating mechanism for said valve mechanism normally biased to- Ward a position wherein said first valve is open and saidv second valve is closed, means providing an oil chamberl in Which oil from the burner can accumulate, a float in said chamber controlvling the operation of said operating mechanism,

and means responsive to the opening of said second valve for discharging oil from said passage into said float chamber.v

16, Control apparatus` for oil burners comprisingva float chamber in vwhich oil from the-l burner can accumulate, a float in said chamber, a pipe line supplying oilfto the burner, valve ply of`.oil to said burner, a float chamber in.

which oil escaping from said burner can accu-v mulate, a float in said chamber for operating said valve mechanism, and means responsive to the operation or" saidvalve mechanism vfor venting oil from said pipe line between the burner and valve mechanism. into said floatchamber.

. 18. Control mechanism for oil burners com-` prisingvalve mechanism for controlling' the supply of oil to the burner, operating mechanism forr said valve mechanism including a pivoted frame,

ythermo-responsive means for holding said frame in a predetermined position and for permitting said frame to move to a second position when said thermo-responsive means operates, a lever pivoted upon said frame engageable with said valve mechanism, and lfluid .levelv control" means for actuating said lever to operate said valve mechanism, said pivoted frame being also constructed and arranged to move said lever and effect the operation of said valve mechanism independentl of saidl fluid level responsive means. 19. Control apparatus vfor oil burners comprising a casing havingy an oil chamber in which escaping oil from the burner ycan accumulate and a cover, said cover having means providing an inlet for pressure oil and an outlet for oil to the burner, valve mechanism y,carried by said cover including a valve for closing said inlet, and a said operating' second'- valve for openingfsaid' outlet toi 'the in"-vl terior of the casing, a lever carried bysaid` cover foroperating said valve mechanism, and a float carried by saidlever and located in said-float chamber'for'operatingsaid lever. 20. Control mechanism for oil burners comprising a casing having an oil chamber in which escaping oil from the burner can accumulate, and a cover,said' cover having means providing an inlet for pressure'oil, and an youtlet forv oil tothe burner, a valve for closing said inlet, a

second valve for opening said outlet to the 'interior of the casing, a lever supporting frame pivotally carried bysaid cover, a thermo-responsive member normally holding said frame in an inoperative position and operating to'permit said frame to move to an operated position, a valve k operating lever pivoted on said frame and having an operative connection with said Valve, and a iioat carried by said lever in said oat chamber.

21. Control mechanism for oil burners comprising a casing having an oil chamber in which f escaping oil from the burner can accumulate, and

a cover, said cover having means providing an inlet for pressure oil, and an outlet for oil to the burner, a valveforclosing said. inlet', a second Valve for opening said outlet to the interior" of the casing, a lever supporting frame pivotally carried by said cover, a thermo-responsive member normally holding said frame in an inoperative position and operating to permit said frame to move to an operated position, a valve operating lever pivoted on said frame and having an operativel connection With said valve, a float,3f l) carried by said lever in said oat chamber, and valve means for withdrawing the oil in said chamber. f

22. Control mechanism for oil burners comescaping oil from the burner can accumulate, and a cover, said coverhaving means providing an `inlet for pressure oil, and an outlet for oil to the burner, a valve for closing said inlet, a sec- `ond valve for opening 'said outlet to the interior of the casing, a leverysupporting frame pivotally carried by said cover,`a thermo-responsive member normally holding said frame in an inoperative position and operating to permit ysaid frame to move to an operated position, a valve operating lever pivoted on said frame and having an operative connection with said valve, a float carried by said lever in said chamber, valve means for .withdrawing oil from said chamber, and

vmeans responsive to the operation'oi saidvalves l for rapidly introducing oil into said float chamber.

. f 23. 'Ihe combinationv of an oil burner, a pump for supplying oil under pressure toL the burner, a motor for operatingsaid pump, a pipe line conducting oil from said pump to said burner, means responsive to a predetermined reduction of pressure of oil in said pipe line for effecting the stoppage of said motor, .and means responsive to anv abnormal discharge of oil from theburner for sure of oil in said pipe line foreiiecting the stoppage of said motor, and means responsive to an abnormal ambient temperature for eecting a `prising a casing having an oil chamber in which reduction of oil pressure in said pipe line sufficient to operate said pressure-responsive means.

25. The combination of an oil burner, a pump for supplying oil under pressure to the burner, a motor for operating said pump, a pipe line conducting oii from said pump to said burner, means responsive to a predetermined reduction of pressure of` oil in said pipe line for effecting the stoppage of vsaid motor, and burner-controlled means operative to vent said pipe line and eiect a reduction of oil pressure in said pipe line sufiicient' to operate said pressure-responsive means.

FORREST R. WHITCOMB. 

